diff options
Diffstat (limited to '')
| -rw-r--r-- | plat/arm/board/corstone700/common/drivers/mhu/corstone700_mhu.c | 117 | ||||
| -rw-r--r-- | plat/arm/board/corstone700/common/drivers/mhu/corstone700_mhu.h | 37 |
2 files changed, 154 insertions, 0 deletions
diff --git a/plat/arm/board/corstone700/common/drivers/mhu/corstone700_mhu.c b/plat/arm/board/corstone700/common/drivers/mhu/corstone700_mhu.c new file mode 100644 index 0000000..832cfb7 --- /dev/null +++ b/plat/arm/board/corstone700/common/drivers/mhu/corstone700_mhu.c @@ -0,0 +1,117 @@ +/* + * Copyright (c) 2019-2022, Arm Limited. All rights reserved. + * + * SPDX-License-Identifier: BSD-3-Clause + */ + +#include <assert.h> + +#include <arch_helpers.h> +#include <common/debug.h> +#include <drivers/delay_timer.h> +#include <lib/bakery_lock.h> +#include <lib/mmio.h> + +#include "corstone700_mhu.h" +#include <plat_arm.h> +#include <platform_def.h> + +ARM_INSTANTIATE_LOCK; + +#pragma weak plat_arm_pwrc_setup + +/* + * Slot 31 is reserved because the MHU hardware uses this register bit to + * indicate a non-secure access attempt. The total number of available slots is + * therefore 31 [30:0]. + */ +#define MHU_MAX_SLOT_ID 30 + +void mhu_secure_message_start(uintptr_t address, unsigned int slot_id) +{ + unsigned int intr_stat_check; + uint64_t timeout_cnt; + volatile uint8_t expiration; + + assert(slot_id <= MHU_MAX_SLOT_ID); + arm_lock_get(); + + /* + * Make sure any previous command has finished + * and polling timeout not expired + */ + + timeout_cnt = timeout_init_us(MHU_POLL_INTR_STAT_TIMEOUT); + + do { + intr_stat_check = (mmio_read_32(address + CPU_INTR_S_STAT) & + (1 << slot_id)); + + expiration = timeout_elapsed(timeout_cnt); + + } while ((intr_stat_check != 0U) && (expiration == 0U)); + + /* + * Note: No risk of timer overflows while waiting + * for the timeout expiration. + * According to Armv8 TRM: System counter roll-over + * time of not less than 40 years + */ +} + +void mhu_secure_message_send(uintptr_t address, + unsigned int slot_id, + unsigned int message) +{ + unsigned char access_ready; + uint64_t timeout_cnt; + volatile uint8_t expiration; + + assert(slot_id <= MHU_MAX_SLOT_ID); + assert((mmio_read_32(address + CPU_INTR_S_STAT) & + (1 << slot_id)) == 0U); + + MHU_V2_ACCESS_REQUEST(address); + + timeout_cnt = timeout_init_us(MHU_POLL_INTR_STAT_TIMEOUT); + + do { + access_ready = MHU_V2_IS_ACCESS_READY(address); + expiration = timeout_elapsed(timeout_cnt); + + } while ((access_ready == 0U) && (expiration == 0U)); + + /* + * Note: No risk of timer overflows while waiting + * for the timeout expiration. + * According to Armv8 TRM: System counter roll-over + * time of not less than 40 years + */ + + mmio_write_32(address + CPU_INTR_S_SET, message); +} + +void mhu_secure_message_end(uintptr_t address, unsigned int slot_id) +{ + assert(slot_id <= MHU_MAX_SLOT_ID); + /* + * Clear any response we got by writing one in the relevant slot bit to + * the CLEAR register + */ + MHU_V2_CLEAR_REQUEST(address); + + arm_lock_release(); +} + +void __init mhu_secure_init(void) +{ + arm_lock_init(); + + /* + * The STAT register resets to zero. Ensure it is in the expected state, + * as a stale or garbage value would make us think it's a message we've + * already sent. + */ + + assert(mmio_read_32(PLAT_SDK700_MHU0_SEND + CPU_INTR_S_STAT) == 0); +} diff --git a/plat/arm/board/corstone700/common/drivers/mhu/corstone700_mhu.h b/plat/arm/board/corstone700/common/drivers/mhu/corstone700_mhu.h new file mode 100644 index 0000000..7f14ca5 --- /dev/null +++ b/plat/arm/board/corstone700/common/drivers/mhu/corstone700_mhu.h @@ -0,0 +1,37 @@ +/* + * Copyright (c) 2019-2022, Arm Limited. All rights reserved. + * + * SPDX-License-Identifier: BSD-3-Clause + */ + +#ifndef CORSTONE700_MHU_H +#define CORSTONE700_MHU_H + +#define MHU_POLL_INTR_STAT_TIMEOUT 50000 /*timeout value in us*/ + +/* CPU MHU secure channel registers */ +#define CPU_INTR_S_STAT 0x00 +#define CPU_INTR_S_SET 0x0C + +/* MHUv2 Control Registers Offsets */ +#define MHU_V2_MSG_CFG_OFFSET 0xF80 +#define MHU_V2_ACCESS_REQ_OFFSET 0xF88 +#define MHU_V2_ACCESS_READY_OFFSET 0xF8C + +#define MHU_V2_ACCESS_REQUEST(addr) \ + mmio_write_32((addr) + MHU_V2_ACCESS_REQ_OFFSET, 0x1) + +#define MHU_V2_CLEAR_REQUEST(addr) \ + mmio_write_32((addr) + MHU_V2_ACCESS_REQ_OFFSET, 0x0) + +#define MHU_V2_IS_ACCESS_READY(addr) \ + (mmio_read_32((addr) + MHU_V2_ACCESS_READY_OFFSET) & 0x1) + +void mhu_secure_message_start(uintptr_t address, unsigned int slot_id); +void mhu_secure_message_send(uintptr_t address, + unsigned int slot_id, + unsigned int message); +void mhu_secure_message_end(uintptr_t address, unsigned int slot_id); +void mhu_secure_init(void); + +#endif /* CORSTONE700_MHU_H */ |